Field of the Invention
The present invention relates generally to an apparatus and method for effecting movement and clearance spacing of a concave relative to the rotor of a combine and, more specifically, to an apparatus and method for providing easy removal of crop material lodged between a rotor and concave and for reducing rotor actuation motor torque and increasing rotor mechanical advantage.
Agricultural combines are well known in the art for harvesting and threshing a number of various agricultural crops, including for example corn, wheat, soybeans, etc. Typically, agricultural combines include a harvesting apparatus, an infeed mechanism, and a separating apparatus. In operation, the harvesting apparatus reaps the crop, which is planted in the ground. After reaping, the infeed mechanism feeds the crop to the separating apparatus.
Usually, the separating apparatus in a rotary combine includes a rotor, which can extend axially or transversely within the body of the combine, and which is surrounded at least in part by a perforated concave having a plurality of apertures. As shown for example in U.S. Pat. No. 5,489,239, titled “Rotary Combine” and issued Feb. 6, 1996 to Case Corporation, the same assignee as for the present application, the concave can include a series of concave inserts arranged in a side-by-side configuration, with each concave insert extending partially circumferentially around the rotor. Usually, it is desirable to provide for an adjustment of the concave, wherein the spacing between the concave and the rotor can be altered to provide for the threshing of different crops in different conditions and removal of lodged crop material.
For example, it is known to pivotally support one end of the concave about an axis, with the other end thereof having linkages that are adjustable for movement of the concave toward and away from the rotor as it pivots about the one end. However, such known linkages allow for only minimal clearance spacing between the concave and the rotor. This limited clearance spacing becomes undesirable when crop material becomes lodged in the area.
As a result, torque on the rotor actuation motor becomes excessive and the mechanical advantage of the rotor decreases. Consequently, mechanical disassembly, which can be a difficult and time-consuming undertaking, may be necessary to free the lodged material from the area between the rotor and the concave.
The drawbacks of the known apparatuses and methods for effecting movement and clearance spacing of a concave relative to the rotor of a combine have been known within the industry without any marked improvement to date. Thus, the need exists for the present invention, which provides an apparatus and method for extending the clearance spacing between a rotor and concave to allow for easy removal of lodged material. Additionally, increased clearance spacing reduces rotor actuation motor torque and increases rotor mechanical advantage.
It is accordingly the primary objective of the present invention that it provide a concave adjustment mechanism and method for effecting movement and clearance spacing of a concave relative to a rotor of a combine.
It is another objective of the present invention that it provide an adjustable rigid concave linkage when a concave is placed in a “fully closed position” and in a “clean-out position” and a flexible concave linkage when the concave is placed in a “fully opened position” (i.e. extended range).
It is yet another objective of the present invention that it provide an extended actuation range to allow for easy removal of lodged material between a concave and a rotor of a combine.
It is yet a further objective of the present invention that it decrease rotor actuation motor torque and increase rotor mechanical advantage.
It is an additional objective of the present invention that it provide a travel limit to prevent a concave from being raised into, and having contact with, a rotor of a combine.
The concave adjustment mechanism apparatus of the present invention must also be of a construction which is both durable and long lasting, and it should also require little or no maintenance to be provided by the user throughout its operating lifetime. In order to enhance the market appeal of the concave adjustment mechanism apparatus and method of the present invention, it should also be of inexpensive construction to thereby afford it the broadest possible market. Finally, it is also an objective that all of the aforesaid advantages and objectives be achieved without incurring any substantial relative disadvantage.